Open the Folders Module. Folders are created from the organization panel using the '+' button at the top.
This opens the 'Create New Folder' box, where you'll enter a folder name and click 'create folder'.
Once created, the folder appears immediately in the organization panel — nested under its parent if you set one, or at the top level if you didn't — along with an item count next to its name, and is ready for items to be added.
Parent and Child Folders
After an initial folder is created, it can be a parent folder to other folders. When creating a new folder, you can choose the location of the folder.